package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.apache.tomcat.jni.File;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/*
* 过滤器包
* 检查用户是否已经完成登录
* 所有路径都拦截
* */
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {

    //路径匹配器,支持通配符
    public static final AntPathMatcher PATH_MATCHER =new AntPathMatcher();
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request=(HttpServletRequest) servletRequest;
        HttpServletResponse response=(HttpServletResponse) servletResponse;
        /*
        * 1.获取本次请求的uri
        * 2.判断本次请求是否需要处理
        * 3.如果不需要处理,则直接放行
        * 4.判断登录状态，如果已登录,则直接放行
        * 5.如果未登录则返回未登录结果
        * */

        //1.获取本次请求的uri
        String requestURI = request.getRequestURI();
        //定义不需要处理的请求路径
        String[] urls=new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**"
        };
        log.info("拦截到的请求：{}",requestURI);

        //2.判断本次请求是否需要处理
        boolean check = check(urls, requestURI);
        //3.如果不需要处理,则直接放行
        if(check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }
        //4.判断登录状态，如果已登录,则直接放行
         if(request.getSession().getAttribute("employee")!=null){
             log.info("用户已登录，用户id为{}",request.getSession().getAttribute("employee"));
             Long empId=(Long) request.getSession().getAttribute("employee");
             BaseContext.setCurrentId(empId);

             filterChain.doFilter(request,response);
             return;
         }
         log.info("用户未登录");
         //5.如果未登录则返回未登录结果,通过输出流的方式向客户端响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }
    /*
    * 路劲匹配，检查本次请求是否需要放行
    * */
    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if(match){
                return true;
            }
        }
        return false;
    }
}
